ShakingAlertView is a UIAlertView subclass with a password entry textfield. Incorrect password entry causes a "shake" animation similar to the OS X account login screen.

Video Demo

Drag the ShakingAlertView/ folder into your project. This contains the UI components and cryptographic helpers necessary for hashing passwords.

Use ShakingAlertView just like UIAlertView. For a checking a plain text password:

ShakingAlertView *shakingAlert = nil;
shakingAlert = [[ShakingAlertView alloc] initWithAlertTitle:@"Enter Password"
                                           checkForPassword:@"pass"];

[shakingAlert setOnCorrectPassword:^{
    // Code to execute on correct password entry
}];

[shakingAlert setOnDismissalWithoutPassword:^{
    // Code to execute on alert dismissal without password entry
}];

[shakingAlert show];
[shakingAlert release];

Rather than using a delegate, pass the instance a completion block to be executed for correct password entry and alert dismissal.

ShakingAlertView uses the Common Crypto C API to hash the entered text to SHA1 or MD5. Therefore if you only know the hashed counterpart of a password string you can specify this along with the hashing algorithm type in the constructor.

ShakingAlertView *shakingAlert = nil;
shakingAlert = [[ShakingAlertView alloc] initWithAlertTitle:@"Enter Password"
                                           checkForPassword:@"W6ph5Mm5Pz8GgiULbPgzG37mj9g=" //sha1 hash of 'password'
                                      usingHashingTechnique:HashTechniqueSHA1];
                                      

The hashing algorithm to use is defined by an enum and passed into the constructor.

typedef enum {
	HashTechniqueNone,
    HashTechniqueSHA1,
    HashTechniqueMD5
} HashTechnique;

HashTechniqueNone is used if no technique is specified, like in the initWithAlertTitle:checkForPassword and initWithAlertTitle:checkForPassword:onCorrectPassword:onDismissalWithoutPassword constructors. Here the entered string is compared with the specified plaintext password using a simple isEqualToString: evaluation.

NSData+Base64.h/m and b64.h/m from aqtoolkit by AlanQuatermain

This code is distributed under the terms and conditions of the MIT license.

Copyright (c) 2012 Luke Stringer

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The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

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